Physics Lesson: Pressure
Many people underestimate the effects of pressure. This is a link to a video taken in 6000 feet of water. An undersea robot is sawing a 3mm wide slit (1/10th of an inch ... remember that width) in a pipeline. The pressure inside the pipeline is 0 psig, while the pressure outside is 2700 psi, or 1.3 tons per square inch. Then a crab comes along....